
!Rubik          E.T.Emms
******

    I presume that everyone is familiar with the Rubik cube - it
was the craze a few years ago!  In its initial state each face of
the cube has only one colour and the 6 faces are each coloured
differently.  A face (slice) may be rotated about its middle and
we create the problem by rotating slices in a random fashion
until the colours are thoroughly mixed. The problem is to restore
the cube to its pristine state. Each of the 6 slices
(Left,Right,Front etc) may be rotated clockwise or anticlockwise
(viewed looking directly at that face). The desired rotation is
chosen by clicking on the appropriate box in the control panel at
top-right. At the bottom of that control panel are boxes enabling
you to 
       a) set up the initial position
       b) scramble the cube. This performs 20 slice rotations,
 the faces being chosen at random.
       c)  restore the cube by 'undoing' the rotations made.
There are algorithms to do this in an 'optimum' fashion but I 
have not attempted to use any of them.                       
     Another interesting activity is to create 'designs'. Try
these: (the notation will be clear when you see the control
panel) 
Shooting Star  (L)(L)(R)(R)(F)(F)(B)(B)
Chequerboard  As above but then follow with (T)(T)(U)(U)
Boxes           (L)(R)(T)(U)(F)(B)(L)(R)

